Car-washing system



Nov. 11, 1930. B. s. AIKMAN CAR WASHING SYSTEM Filed May 26, 192? 2Sheets-Sheet 1 CAR WASHING ST STEM Filed May 26, 1927 2 Sheets-Sheet 2 Patented Nov. 11, 1930 Umran STA-res PATENT FFLICE BURTON s. AIKMAN, or MILWAUKEE, WISGON$IN AssieNon T NATIONAL BRAKE &

ELECTRIC COMPANY, OF MILwAUKEnwrsooNsm, A CORPORATION OF WISCONSIN CAR-WASHING SYSTEM 1 A 'Application filed May 26,

My invention relates to washing systems such as are employed for washing automobiles with a fluid jet comprising a spray of water projected and broken up by compressed air. While I shall describe my invention as embodied in such a car Washing system, I do not intend to be limited to theparticular use to which the same is put. A

According to the present invention, I provide a source of air under pressure and a source of water under pressure, and I provide means for maintaining an accurate relation of the pressure so that a suitable fine spray of water moving at high velocity may be secured for wetting the surface to be cleaned and for flushingthe surface with the requiredforceto remove all grit, sand, dirt and the like, and leave the surface completely clean and unclouded.

A high velocity jet of water alone is not suitable. If there is sand or grit on the, surface to be cleaned, a high velocity jet of solid water will tend to cut the finish. Also, too much water is wasted,jsince the water does not have the spreadingpower nor the required area, and if it is attempted to break the water jet by projecting the samethrough a fine nozzle, such as a rosenozzle, the open-, ings will be quickly clogg'edby any minor]:I 1m-; ur-' purities which maybe in the water. thermore, it appears that the presence of the stream of'air in the spray has the highly benf eficial effect in driving the film of water:

along the surface in. a manner tending constantly to clean the same. That is to say, in

' the spray which is produced by a nozzle of this character, a separate drop of water arrives on'a given area and the surface is wet-- ted andimmediately thereafter the film ofv water whichis thusdeposited on thesurface is moved laterally by thewiping action of the stream of airv.This is followed by the wetting of the same surface-with a succeed ing drop and again the WlPlIlg, act on of the i 45;

air. It will be seen, therefore, that the spray produced by a system ofz-this kind has the surface very rapidly capability of cleaning a and efiectively. V 1

The success of the operation depends upon breaking the water up into drops andspread- 1927. Serial No. 194,283.

ter the orifices-and passages through which these fluids travel are once fixed, operation of the system will give substantially uniform results under all. conditions. i

Preferably, in accordance with my inven tion, the water pressure iscontrolled by the air pressure. It is, however, within the spirit of my invention to control the air pressure in accordance with thewater pressure, so that a uniform relation is maintained between them. V a

' There the compressed air is supplied from a tank, or reservoir charged by a compressor, there isa tendency for the'pressure of the air to fluctuate between certain limits, particularly in a small installation.

Qbviously, without departing from my in vention, the air may be compressed to a suitable value above the required pressure, even with widefluctuations, and areducing valve employed'between the reservoir and the line 5 i pressure substantially uniform, but the mere 'maintenance of the air pressure alone is'not all that is required. Theremust be an intercontrol betweenthe two fluids so'that for best results the pressure ratio between them should be uniform. I i V y I prefer to, let the air pressure vary within reasonable limits, and causeitto exert a control over the water pressure. A source;

of water supply is provided which is capable of delivering water at-la pressure'not substantially lower than the maximum pressure of air-delivered, and by a suitable valve under thecontrol of the air pressure the delivery pressure of the water is varied to keep a definite relation, preferably equality, with the air pressure. This relation, obviously, maybe reversed.) I Y a opening of the valve and discharge the same through the pipe 25, connection 23, to the mixing chamber 5. The spring is so graduated to the normal air pressure and diaphragm area as to regulate the Water delivery to be substantially equal to the air delivery pressure. If the pressure of the air is slightly above normal, the plunger 36 and valve 30 will be depressed, and a larger amount of water permitted to enter the pump 3, with a resulting increase in the delivery pressure in the water conduit 25.

Assume that the parts are in the position shown in Fig. 1 and that the motor 4 and pump 3 are in operation, as soon as pressure is applied to the diaphragm 36 the valve 30 will be opened to a degree permitting the building up of pressure on the delivery side of the pump equal to the air pressure. Air passes down through the nozzle 8 and is discharged at the opening 9 towards the outlet to the pipe 15. Water enters by the connection 23 and it tends to spray into the chamher 5 and whirl rotarily about the outlet opening 15 in a substantially uniform manner, the two fluids mixing-so as to break up the solid stream of water and dropping through the pipe 15 and hose 19 and escaping simultaneously at the constricted opening 21 in the gun 6. The result is a high velocity spray of drops of water andair which wet and scour the surface to be cleaned with great efi'ectiveness It is customary to operate two guns, one on each side of the car being washed where washing operation is carried on in a large scale. Where two or more guns are to be operated from a system such as shown in Fig. 1, it is preferable that the delivery pressure of the water be impressed upon the bottom of the diaphragm 36 so that theposition of the valve 30 will be determined by' a comparison of the pressure of the two fluids as they are delivered to the mixing chambers. 1

While I have shown a centrifugal pump for providing the necessary water pressure, it is to be understood that any suitable means for providing the desired pressure and delivery of water may be substituted, as, for

example, a positive displacement pump of the reciprocating piston type. I

In Fig. 21 have indicated a system in which a reciprocating piston type of pump is employed for furnishing the necessary liqbooster, operatedby the pressure ofthe city mains for raising the pressure of water delivered from the. city mains'to the desired delivery pressure. Thejsupply pipe 41"leading from the city mains 2 has two branches 48 and 49z'leading to theimotor and pump control of the regulating valve 29",.is delivered to 'the;chamber 5 at a pressure'subst'antiallyequalto the air pressure. In this case the ibottom' side oi-the diaphragm is subjected, to. the pressure existing-in the pipe 51, which is on the delivery side of the valve 29; Provision for introducing the pressure below thediaphragm' 36 is made by fluting the stem 3-1 to permit thepressure in the pipe 51to-1act uponithe bottom" side of the diaphragm. The diaphragm istherefore balanced between the air pressure and the pressure of the water in the delivery pipe 51,

the valve 30 being "held normally closed by the pressure ofthe spring 35. i The pressure of thespring 35 is'relatively'light andfmay be adjusted to anyi'desired value: 'So long as the system is inoperation the. valve30 is held awayfifrom.its'seatbythe slight preponderance: of; air: pressure required I, to oppose thespring 35j In other respe ctspthe' system shown inFig.

2 is the same as described. and disclosed in connection with Fig. 1.; I Absoluteequality between the air and'water pressure is'notessential tothe practice of the invention, but it is desirable that the pressures, if they vary, should vary together, so that the efiectiven'essof the spray at the nozzle of the gun will be as great as is permissible with the pressures available.

While I have shown in Fig. 2 the valve 29 inserted in the water delivery piperfor regulating the water flow in accordance with variations of air pressure, it is to be understood that itis within my invention to insert the said valve in the air delivery line 13 .and to control'the same in accordance with variations of water 'pressure'if so desired.

Furthermore, I do not intend to be limited I to the specific mixing and delivery mecha- Y nism which I have described, although for this service the apparatus described has operated satisfactorily. For example, as shown in Fig. 3, I may provide the mixing chamber 5 within the nozzle 21 and lead the water I and the air in by concentric pipes 53 and, 54,

respectively, the mixture of air and water leaving the gun 6 through the orifice or'noza I zle 21 as a blast ofair carrying drops of I water. Where the form of mixing chamber shown in Fig. 3 is employed, the pipes 53 and-54 may run horizontally any desired distance without danger of slugging, since the 

